CH26 HW #4:

Calculate Lead Time Flint Fabricators Inc. machines metal parts for the automotive industry. Under the traditional manufacturing approach, the parts are machined through two processes: milling and finishing. Parts are produced in batch sizes of 30 parts. A part requires 5 minutes in milling and 7 minutes in finishing. The move time between the two operations for a complete batch is 5 minutes. Under the lean philosophy, the part is produced in a cell that includes both the milling and finishing operations. The operating time is unchanged; however, the batch size is reduced to 4 parts and the move time is eliminated. Determine the value-added, non-value-added, and total lead times, and the value-added ratio under the traditional and lean manufacturing methods. If required, round percentages to one decimal place.

Calculate Lead Time Flint Fabricators Inc. machines metal parts for the automotive industry. Under the traditional manufacturing approach, the parts are machined through two processes: milling and finishing. Parts are produced in batch sizes of 30 parts. A part requires 5 minutes in milling and 7 minutes in finishing. The move time between the two operations for a complete batch is 5 minutes. Under the lean philosophy, the part is produced in a cell that includes both the milling and finishing operations. The operating time is unchanged; however, the batch size is reduced to 4 parts and the move time is eliminated. Determine the value-added, non-value-added, and total lead times, and the value-added ratio under the traditional and lean manufacturing methods. If required, round percentages to one decimal place. Feedback Check My Work Recall that lead time can be classified as one of the following: 1. Value-added lead time, which is the time spent in converting raw materials into a finished unit of product. 2. Non-value-added lead time, which is the time spent while the unit of product is waiting to enter the next production process or is moved from one process to another. In this exercise for Traditional: Value-added processing time = Milling time + Finishing time Non-value-added time = Total within-batch wait time + Move time, where Total Within-Batch Wait Time =( Total Time to Perform Operations ) x (Batch Size - 1) Add value-added processing time + non-value-added processing time to obtain total processing time. Calculate Value-Added Ratio = Value-Added Process Time Total Process Time In this exercise for Lean Manufacturing: Value-added processing time = Milling time + Finishing time Non-value-added time = Total within-batch wait time, where Total Within-Batch Wait Time is obtained by multiplying the process time by the remaining units in the batch (waiting their turn)